Dual spherical ball clamp

ABSTRACT

A dual spherical ball clamp is employed to allow for pivotal adjustment of a robotic arm to support an object in a desired position. The clamp is formed by a pair of clamp halves bolted together to form a pair of sockets. Each socket receives a spherical ball of an arm. The edges of the dual spherical ball clamp are slightly inclined outwardly with respect to the lower surface of the dual spherical ball clamp to provide for additional range of motion of the arms.

[0001] This application claims priority to provisional applicationserial No. 60/259,686 filed Jan. 4, 2001.

BACKGROUND OF THE INVENTION

[0002] Robotic arms often employ a ball and socket joint to allow forpivotal adjustment of the robotic arm in order to support an object in adesired position. In a ball and socket joint, a ball is received in acomplementary socket of a socket component. Movement of the ball withinthe socket allows for pivotal movement of the ball and an attached arm.Securing the ball and socket joint creates a rigid arm capable ofsupporting an object.

[0003] In prior ball and socket joints, the arm has a relatively largediameter when compared to the diameter of the ball. Often, the largediameter of the arm creates an obstruction between the socket and thearm, hindering movement of the arm and reducing the range of motion ofthe robotic arm.

[0004] Hence, there is a need in the art for an improved ball and socketjoint utilized on a robotic arm.

SUMMARY OF THE INVENTION

[0005] The dual spherical ball clamp of the present invention increasesthe range of motion of a robotic arm. The dual spherical ball clampincludes a pair of clamp halves secured together by bolts to form a pairof sockets. When assembled, a small gap is formed between the clamphalves.

[0006] Each socket receives a ball attached to an arm. The balls aremade of a harder material than the material of the complementarysockets, allowing the sockets to better conform to the ball. Preferably,the sockets are made of aluminum. Additionally, the sockets surround theball beyond the center of gravity of the ball, or over more than onehalf of the outer periphery of the ball, providing a greater holdingforce of the ball within the socket.

[0007] The edges of the dual spherical ball clamp are slightly inclinedupwardly with respect to the lower surface of the clamp to provide anincreased range of motion of the pivoting arms. Preferably, the edgesare inclined 75° from the lower surface of the clamp.

[0008] Preferably, the clamp halves are secured together by either twobolts or four bolts. If four bolts are employed, a bolt is located aboveand below each of the sockets. The distance of the gap at one socket candiffer from the distance of the gap at the other socket by adjusting thetightening of the bolts proximate to each socket. With the clamp halvessecured, the clamp is locked, creating a rigid arm capable of supportingan object.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The various features and advantages of the invention will becomeapparent to those skilled in the art from the following detaileddescription of the currently preferred embodiment. The drawings thataccompany the detailed description can be briefly described as follows:

[0010]FIG. 1 illustrates a perspective view of the dual spherical ballclamp of the present invention utilized on a robotic arm;

[0011]FIG. 2 illustrates a side view of one clamp half of the dualspherical ball clamp;

[0012]FIG. 3 illustrates a side view of one clamp half of a secondembodiment of the dual spherical ball clamp;

[0013]FIG. 4 illustrates a perspective view of one clamp half of thedual spherical ball clamp of FIG. 3; and

[0014]FIG. 5 illustrates a front view of the dual spherical ball clampof FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0015]FIG. 1 illustrates a robotic arm 20 employing the dual sphericalball clamp 22 of the present invention for pivotal adjustment of therobotic arm 20 to support an object in a desired position. The dualspherical ball clamp 22 includes a first clamp half 24 and an opposingsecond clamp half 26 which are secured together by bolts 40 to form apair of sockets 28. Each socket 28 receives a spherical ball 30 attachedto an arm 32. Securing the ball 30 and the socket 28 by tightening thebolts 40 creates a rigid robotic arm 20 capable of supporting theobject. Preferably, each ball 30 is approximately 1.75 inch in diameter,and the arm 32 is approximately 1.25 inch in diameter.

[0016] As illustrated in FIG. 2, the edges 34 of the dual spherical ballclamp 22 are slightly inclined upwardly with respect to the lowersurface 36 of the dual spherical ball clamp 22. Each edge 34 is inclinedA degrees from the lower surface 36 of the clamp 22. Preferably, theedges 34 are inclined approximately 75°. The inclined edges 34 allow foradditional range of motion of the arms 32 as a smaller angle B can beformed between the arms 32. Each arm 32 has a large range of motion,preferably at least 90°.

[0017] Clamp half 22 includes a pair of apertures 38 which align with apair of apertures 38 in the opposing clamp half 24 when assembled. Theapertures 38 are located substantially between the pair of sockets 28.Returning to FIG. 1, a bolt 40 passes through the aligned apertures 38to secure the halves 22 and 24 of the dual spherical ball clamp 22together and to secure the balls 30 in the sockets 28. When assembled, asmall gap 142 (shown FIG. 5) is formed between the clamp halves 22 and24.

[0018] The balls 30 are made of a material which harder than thematerial of the complementary sockets 28, allowing the sockets 28 toconform around the ball 30 and increasing holding power of the dualspherical ball clamp 22. Preferably, the sockets 28 are made ofaluminum. However, the dual spherical ball clamp 22 can be made of anymaterial which is softer than the balls 30. The ball 30 could also havea serrated surface to provide greater holding force between the ball 30within the socket 28.

[0019] Additionally, the sockets 28 surround the balls 30 beyond thecenter of gravity 44 of the balls 30. Stated another way, the sockets 28extend over more than half of the outer periphery of the balls 30. Thisprovides a greater holding force, but does present the problem ofpotentially limiting the relative movement of the arms 32, and henceresults in the beneficial attributes of the inclined edges 32.

[0020] Although a robotic arm 20 employing a dual spherical ball clamp22 is described, it is to be understood that a plurality of dualspherical ball clamps 22 can be employed to provide for additionalmovement of the robotic arm 20.

[0021] In another embodiment of the present invention, as illustrated inFIGS. 3-5, four apertures 138 are located in each clamp half 122 and 124of the dual spherical ball clamp 120. Each of the four apertures 138 inthe first clamp half 122 align with one of the four apertures 138 in thesecond clamp half 124. One aperture 138 is located both above and beloweach of the sockets 128. Tightening or loosening the bolts 140 proximateto a desired socket 128 allows for adjustment of the gap 142 at a socket128. The distance of the gap 142 at one socket 128 can differ from thedistance of the gap 142 at the other socket 128. Adjusting the distanceof the gap 142 at a desired socket 128 allows one of the arms 138 to bepivoted while the other arm 138 remains locked. Additionally, employingfour bolts 140 provides for greater holding strength of the clamp halves122 and 124 together.

[0022] The foregoing description is exemplary of the principles of theinvention. Many modifications and variations of the present inventionare possible in light of the above teachings. The preferred embodimentsof this invention have been disclosed, however, so that one of ordinaryskill in the art would recognize that certain modifications would comewithin the scope of this invention.

What is claimed is:
 1. A ball and socket assembly comprising: a socketcomponent including a pair of sockets and a pair of opposed inclinededges; and a ball component received in each of said pair of opposingsockets.
 2. The assembly as recited in claim 1 wherein said ballcomponent includes a ball and an arm, and said ball is received in saidsocket to allow for pivotal adjustment of said arm.
 3. The assembly asrecited in claim 2 wherein said balls are approximately 1.75 inch indiameter and said arms are approximately 1.25 inch in diameter.
 4. Theassembly as recited in claim 2 wherein said balls are made of a materialharder than a material of said sockets.
 5. The assembly as recited inclaim 4 wherein said sockets are made of aluminum.
 6. The assembly asrecited in claim 2 wherein said sockets extend over move than one halfof a surface area of said balls.
 7. The assembly as recited in claim 1wherein said socket component includes a first socket half and a secondsocket half secured together to form said pair of sockets.
 8. Theassembly as recited in claim 7 wherein said clamp halves are securedtogether by a pair of bolts located substantially between said pair ofsockets.
 9. The assembly as recited in claim 7 wherein said clamp halvesare secured together by four bolts, one of said bolts being locatedsubstantially over one of said sockets, another of said bolts beinglocated substantially under said socket, one of said bolts being locatedsubstantially over the other of said sockets, and one of said boltsbeing located substantially under the other of said sockets.
 10. Theassembly as recited in claim 7 further including a gap between saidclamp halves.
 11. The assembly as recited in claim 1 wherein said pairof opposed edges are inclined approximately 75° from a lower surface ofsaid assembly.
 12. The assembly as recited in claim 1 wherein said ballsare serrated.
 13. A robotic arm comprising: a ball and socket assemblyincluding a socket component having a first socket half and a secondsocket half secured together to form a pair of sockets and a pair ofopposed inclined edges, and a pair of ball components each having a ballreceived in one of said sockets and an arm, movement of said ball insaid socket allowing for pivotal adjustment of said arm.
 14. The roboticarm as recited in claim 13 wherein said balls are approximately 1.75inch in diameter and said arms are approximately 1.25 inch in diameter.15. The robotic arm as recited in claim 13 wherein said balls are madeof a material harder than a material of said sockets.
 16. The roboticarm as recited in claim 13 wherein said clamp halves are securedtogether by a pair of bolts located substantially between said pair ofsockets.
 17. The robotic arm as recited in claim 13 wherein said clamphalves are secured together by four bolts, one of said bolts beinglocated substantially over one of said sockets, another of said boltsbeing located substantially under said socket, one of said bolts beinglocated substantially over the other of said sockets, and one of saidbolts being located substantially under the other of said sockets. 18.The robotic arm as recited in claim 13 further including a gap betweensaid clamp halves.
 19. The robotic arm as recited in claim 13 whereinsaid robotic arm includes a plurality of said ball and socketassemblies.
 20. The robotic arm as recited in claim 13 wherein said pairof opposed ends are inclined approximately 75° from a lower surface ofsaid assembly.
 21. The robotic arm as recited in claim 13 wherein saidballs are serrated.
 22. A method for supporting an object with a roboticarm comprising the steps of: providing a socket component including apair of sockets and a pair of opposed inclined edges; and providing aball component including an arm and a ball which is received in each ofsaid opposing sockets; pivoting said ball in said socket to allow forpivotal adjustment of said arm; and locking said ball in said socket.